Document feeder and image forming apparatus

ABSTRACT

A document feeder includes a document placing tray on which a document is placed; a document discharging tray on which a document discharged from a document discharging port in a discharging direction is stacked; and a light source that radiates light to the document discharging tray. The document discharging tray is disposed below the document placing tray. The document discharging tray has a protruding portion protruding upward from the surrounding area. The light source is disposed within a region having a width that is the same as a document having a maximum size in the width direction.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a document feeder that transports adocument and an image forming apparatus.

Description of the Background Art

A known document feeder disposed in an image forming apparatus takes ina document placed on an input tray, and outputs the document into anoutput tray after the document is read. In the document feeder, theinput tray is disposed above the output tray. Consequently, the outputtray is dark, and sometimes the user fails to notice documents outputinto the dark output tray. Alight source that emits light to the outputtray has been proposed to prevent such a document to be left unnoticed(for example, Japanese Unexamined Patent Application Publication No.2013-197725).

The image reader according to Japanese Unexamined Patent ApplicationPublication No. 2013-197725 includes a document chute that holdsdocuments; a document transporter that transports a document placed onthe document chute; a document stacker that is disposed directly belowthe document chute, and receives a document output by the documenttransporter; and an illuminating unit (illuminating lamp) that isdisposed below the document chute, and radiates light onto the documentstacker. The illuminating unit is disposed orthogonal to the documenttransport direction and in an area outside the document path for adocument having the maximum size. In the image reader, light is radiatedon the document stacker but not on the document. The document notilluminated with light is unnoticeable.

An object of the present invention, which has been conceived to solvethe issue described above, is to provide a document feeder and an imageforming apparatus that can spotlight a document so as to make thedocument more noticeable by a user.

SUMMARY OF THE INVENTION

A document feeder according to the present invention includes a documentplacing tray on which a document is placed; a document discharging traydisposed below the document placing tray, the document discharged from adocument discharging port in a discharging direction being stacked inthe document discharging tray; and a light source disposed below thedocument placing tray and radiating light to the document dischargingtray, the document discharging tray having a protruding portionprotruding farther upward than a surrounding area, the light sourcebeing disposed in a width direction orthogonal to the dischargingdirection in a region having a width smaller than the width of adocument having a maximum size.

In the document feeder according to the present invention, the apex ofthe protruding portion and the light source may be disposed in a regionlocated on a further front side of the document feeder in comparisonwith a center of the document discharging tray in the width directionand extending to a position corresponding to an edge of the documenthaving a maximum size.

In the document feeder according to the present invention, the lightsource may be disposed in the width direction in a region from an end ofthe protruding portion on a front side of the document feeder to an edgeof the document having a maximum size on the front side of the documentfeeder.

In the document feeder according to the present invention, the documentplacing tray may have a cutout portion on an edge that is locateddownstream in the discharging direction and on a front side of thedocument feeder in the width direction, and the light source may bedisposed on a peripheral edge along the cutout portion.

In the document feeder according to the present invention, the lightsource may be disposed at a position on the document placing tray withinthe width of the cutout portion in the discharging direction.

In the document feeder according to the present invention, the cutoutportion may be so provided in the width direction as to extend fartherrearward of the document feeder than an end of the protruding portion upto a rear side of the document feeder.

In the document feeder according to the present invention, a transparentor translucent member may be fixed to the cutout portion.

In the document feeder according to the present invention, a wallvertically erected may be disposed at an end of the protruding portionin the width direction.

In the document feeder according to the present invention, the documentdischarging tray may have a depressed portion depressed farther downwardthan the surrounding area, and the depressed portion may be disposedadjacent to the protruding portion in the width direction.

The document feeder according to the present invention may furtherinclude a vertical wall disposed on a front side of the document feederin the width direction along a periphery of the document feeder, inwhich the vertical wall is lower than an apex of the protruding portion.

A document feeder according to the present invention includes a documentplacing tray on which a document is placed; a document discharging traydisposed below the document placing tray, the document discharged from adocument discharging port along the discharging direction being stackedin the document discharging tray; and a light source disposed below thedocument placing tray and radiating light to the document dischargingtray, wherein the document placing tray includes a cutout portion on anedge that is located downstream in the discharging direction and on afront side of the document feeder in the width direction, and the lightsource is disposed at a position on the document placing tray overlayingthe cutout portion in the discharging direction.

An image forming apparatus according to the present invention includesthe document feeder according to the present invention.

According to the present invention, a document stacked on a documentdischarging tray is irradiated with light. Thus, the document isnoticeable, and the user is provided with a better view of the document.The document discharging tray has a protruding portion that lifts aportion of the document, causing the document to curve. This causeslight to be reflected at the document in a way that makes the documentnoticeable by the user.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic side view of an image forming apparatus accordingto a first embodiment of the present invention;

FIG. 2 is a perspective view of a document feeder according to the firstembodiment of the present invention;

FIG. 3 is a top view of the document feeder illustrated in FIG. 2;

FIG. 4 is a front view of the document feeder illustrated in FIG. 2;

FIG. 5 is a side view of the document feeder illustrated in FIG. 2;

FIG. 6 is an enlarged bottom view of a light-source housing and itsvicinity;

FIG. 7 is a schematic side view of a light source arranged in relationto a document discharging tray;

FIG. 8 is a schematic side view of a light source arranged in relationto a document discharging tray according to a second embodiment of thepresent invention;

FIG. 9 is a schematic side view of a light source arranged in relationto a document discharging tray according to a third embodiment of thepresent invention; and

FIG. 10 is a schematic side view of a light source arranged in relationto a document discharging tray according to a modification of the thirdembodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment

An image forming apparatus according to a first embodiments of thepresent invention will now be described with reference to theaccompanying drawings.

FIG. 1 is a schematic side view of an image forming apparatus 100according to the first embodiment of the present invention.

The image forming apparatus 100 is a multifunction peripheralfunctioning as a scanner, a copier, a printer, a facsimile machine, etc.The image forming apparatus 100 sends an image of a document read by animage reader 90 to an external device (i.e., functions as a scanner),and forms a multicolor or monochrome image of the read document or animage received from an external device on a sheet (i.e., functions as acopier, a printer, and a facsimile machine).

The image reader 90 supports an automatic document feeder (an AutoDocument Feeder (ADF)) 120 so as to allow the document feeder 120 to befreely opened and closed. The image reader 90 includes an image readingunit 93 including a light source or an image pickup device, and reads animage of a document. When the document feeder 120 is opened, a documenttable 92 in the upper portion of the image reader 90 is exposed to allowa document (sheet) to be manually placed on the document table 92. Thedocument feeder 120 automatically transports the document as placed tothe image reader 90. The image reader 90 reads the manually placeddocument or the document transported by the document feeder 120, andgenerates image data. Note that the detailed structure of the documentfeeder 120 will be described below with reference to FIGS. 2 to 5.

The image forming apparatus 100 includes an exposure unit 1, developingunits 2, photosensitive drums 3, cleaners 4, chargers 5, anintermediate-transfer-belt unit 6, a fixing unit 7, a sheet feeder tray81, a manual feed tray 82, a sheet output tray 91, and a sheet path S.The image forming apparatus 100 forms a multicolor or monochrome imageon a predetermined sheet in accordance with image data from an externaldevice.

The image data processed by the image forming apparatus 100 correspondsto a color image in the colors black (K), cyan (C), magenta (M), andyellow (Y). Hence, four image stations are provided to form four latentimages in black, cyan, magenta, and yellow. The image stations for therespective colors each includes a developing unit 2, a photosensitivedrum 3, a charger 5, and a cleaner 4.

The photosensitive drums 3 are disposed at the substantial center of theimage forming apparatus 100. The chargers 5 uniformly charge thesurfaces of the corresponding photosensitive drums 3 to a predeterminedpotential. The exposure unit 1 exposes the surfaces of thephotosensitive drums 3 to form electrostatic latent images. Thedeveloping units 2 develop the corresponding electrostatic latent imageson the surfaces of the corresponding photosensitive drums 3, and formtoner images on the surfaces of photosensitive drums 3. Through theseries of operations described above, toner images of the respectivecolors are formed on the surfaces of the photosensitive drums 3. Thecleaners 4 remove and collect the toners remaining on the surfaces ofthe photosensitive drums 3 after development and image transfer.

An intermediate-transfer-belt unit 6 is disposed above thephotosensitive drums 3, and includes an intermediate transfer belt 61,an intermediate-transfer-belt driving roller 62, anintermediate-transfer-belt driven roller 63, intermediate rollers 64,and an intermediate-transfer-belt cleaner 65. Four intermediate transferrollers 64 are provided for the image station for YMCK colors.

The intermediate transfer belt 61 is extended across theintermediate-transfer-belt driving roller 62, theintermediate-transfer-belt driven roller 63, and the intermediatetransfer rollers 64, such that the surface of intermediate transfer belt61 is moved in a predetermined direction (direction of arrow D in thedrawing) by the rollers.

While the intermediate transfer belt 61 moves in the direction of arrowD, the intermediate-transfer-belt cleaner 65 removes and collects theresidual toners, and the toner images of the respective colors on thesurfaces of the photosensitive drums 3 are sequentially transferred andoverlaid with each other on the surface of the intermediate transferbelt 61 so as to form a color toner image on the surface of theintermediate transfer belt 61.

The image forming apparatus 100 further includes a secondary transferunit 10 including a transfer roller 10 a. A nip is defined between thetransfer roller 10 a and the intermediate transfer belt 61. A sheettransported through the sheet path S is fed through the nip. When thesheet passes through the nip, the color toner image on the surface ofthe intermediate transfer belt 61 is transferred onto the sheet.

The sheet feeder tray 81 stores sheets to be used for image formation,and is disposed below the exposure unit 1. The manual feed tray 82 isdisposed on a side face of the image forming apparatus 100 so as to befreely opened and closed. When the manual feed tray 82 is opened, sheetsto be used for image formation can be placed in the manual feed tray 82.The document discharging tray 91 is disposed in the upper portion of theimage forming apparatus 100, and receives the sheets on which imageshave been formed.

The sheet path S includes an S-shaped main path S1, and a reverse pathS2 that branches from the main path S1 and rejoins the main path S1. Apickup roller 11 a, a manual-feed pickup roller 11 b, pre-registrationrollers 12 a, registration rollers 13, the secondary transfer unit 10,the fixing unit 7, and output rollers 12 b are disposed along the mainpath S1. The reverse path S2 branches from the main path S1 between thefixing unit 7 and the output rollers 12 b, passes through reverserollers 12 c and 12 d, and rejoins the main path S1 between thepre-registration roller 12 a and the registration rollers 13.

The pickup roller 11 a is a lead-in roller that is disposed near the endof the sheet feeder tray 81, and feeds each sheet in the sheet feedertray 81 to the sheet path S. The registration rollers 13 temporarilyhold the sheet transported from the sheet feeder tray 81, and feeds thesheet to the transfer roller 10 a at a timing that aligns the front edgeof the sheet and the front edge of the toner image on the photosensitivedrums 3. The pre-registration rollers 12 a are small auxiliary rollersthat support the transportation of the sheet.

The fixing unit 7 includes a fixing roller 71, a pressing roller 72 thatpresses the fixing roller, and a heater 73 that heats the fixing roller71. The fixing unit 7 receives the sheet having the unfixed toner image.The sheet is transported between the fixing roller 71 and the pressingroller 72 for fixing. The sheet having the fixed toner image is outputby the output rollers 12 b into the document discharging tray 91.

When an image is also to be formed on the back face of the sheet, theoutput rollers 12 b send the sheet in the opposite direction into thereverse path S2, where the sheet is flipped over. The flipped sheet isresent to the registration rollers 13. An image is formed on the backface of the sheet in the same manner as that formed on the front face.The sheet is then discharged into the document discharging tray 91.

FIG. 2 is a perspective view of the document feeder 120 according to thefirst embodiment. FIG. 3 is a top view of the document feeder 120illustrated in FIG. 2. FIG. 4 is a front view of the document feeder 120illustrated in FIG. 2. FIG. 5 is a side view of the document feeder 120illustrated in FIG. 2.

The document feeder 120 according to the first embodiment of the presentinvention includes a document placing tray 130 on which a document isplaced, and a document discharging tray 140 on which the documentdischarged from a document discharging port 151 in a dischargingdirection H is stacked.

In the document feeder 120, a transporter 153 is disposed at one end(the left end in FIG. 3) in a horizontal direction X (the left-rightdirection in FIG. 3) along the front side of the document feeder 120,and the document placing tray 130 and the document discharging tray 140are disposed on the other end (the right end in FIG. 3). A documentplacing tray 130 and the document discharging tray 140 are disposedadjacent to each other along the height direction Z. The documentplacing tray 130 is disposed on the top, and the document dischargingtray 140 is disposed on the bottom. That is, the document placing tray130 extends from a document input port 154 disposed in the upper portionof the transporter 153 to the other end of the document feeder 120. Thedocument discharging tray 140 extends from the document discharging port151 disposed in the lower portion of the transporter 153 to the otherend of the document feeder 120. Hence, the input direction (the leftwarddirection in FIG. 3) of the document transported from the documentplacing tray 130 is opposite to the discharging direction H (therightward direction in FIG. 3) of the document transported to thedocument discharging tray 140.

In the document feeder 120, a document placed on the document placingtray 130 enters the transporter 153 through the document input port 154.The document in the transporter 153 is read by the image reader 90, anddischarged from the transporter 153, through the output rollers 152disposed at the document discharging port 151 onto the documentdischarging tray 140. In the description below, the direction orthogonalto the discharging direction H may also be referred to as “widthdirection Y” (the vertical direction in FIG. 3).

The document placing tray 130 is obliquely disposed such that the endadjacent to the document input port 154 is lower than the end (documentplacing tray extension end 130 a) remote from the document input port154. That is, the document placing tray 130 is obliquely disposed so asto allow a document placed on the document placing tray 130 to slideinto the document input port 154 by its own weight.

The document discharging tray 140 is obliquely disposed at substantiallythe same tilt angle as the document placing tray 130 such that the end(document discharging tray extension end 140 a) remote from the documentdischarging port 151 is disposed higher. When a document is dischargedfrom the document discharging port 151, the document is slightlyaccelerated in the discharging direction H by the output rollers 152.The accelerated document is prevented from falling out of the documentdischarging tray 140 by causing the document to slide back toward thedocument discharging port 151. By sliding back, documents are aligned onthe document discharging tray 140. Note that the document placing tray130 and the document discharging tray 140 may have different tiltangles.

The document placing tray 130 has a cutout portion 131 on the downstreamside in the discharging direction H (the right side in FIG. 3) and theedge of the front side of the document feeder 120 in the width directionY (the bottom side in FIG. 3). The document placing tray 130 overlapsthe document discharging tray 140 in plan view (for example, in FIG. 3)such that the document discharging tray 140 is exposed through thecutout portion 131. Note that in the description below, the front sideof the document feeder 120 (the image forming apparatus 100) may also bereferred to as “forward side” in the width direction Y, and the rearside of the document feeder 120 as “rearward side” (the top side in FIG.3).

As illustrated in FIG. 3, the document placing tray 130 has asubstantially rectangular shape in plan view. The cutout portion 131 isprovided in the document placing tray 130 in an area corresponding to acorner of the document placing tray 130. The outer rim of the documentplacing tray 130 along the cutout portion 131 has a first side 131 amore or less extending along the horizontal direction X, and a secondside 131 b more or less extending along the width direction Y. That is,the first side 131 a is disposed on the rearward side (the top side inFIG. 3) of the side of the document placing tray 130 along thehorizontal direction X (the bottom side in FIG. 3). The second side 131b is disposed more upstream (the left side in FIG. 3) than the side ofthe document placing tray 130 along the width direction Y. FIG. 3illustrates a cutout region KR in the discharging direction H defined bythe first side 131 a and the second side 131 b. The cutout region KRcorresponds to the range in which the cutout portion 131 is disposed.

It is presumed that the image forming apparatus 100 is normally operatedby a standing user facing the front side of the image forming apparatus100. Thus, the operation panel, etc., are disposed on the front side.The image forming apparatus 100 is designed to facilitate manual removaldocument and sheets from the front side.

The bottom face of the document placing tray 130 has a light-sourcehousing 132 accommodating a light source 160 near the cutout portion131. The light-source housing 132 is disposed near the outer rim of thedocument placing tray 130 along the cutout portion 131 on the slightlyrearward side of the cutout portion 131. The structure the light-sourcehousing 132 will be described with reference to FIG. 6.

The document discharging tray 140 is obliquely disposed such that thedocument discharging tray extension end 140 a is higher than the otherend. A tilted face is defined by the tilt angle of the documentdischarging tray 140. The tilted face of the document discharging tray140 has a protruding portion 141 and a depressed portion 142 that havepartially different heights in the height direction Z. Note that theshapes of the protruding portion 141 and the depressed portion 142 willbe described in detail below with reference to FIG. 7.

The document discharging tray 140 has a vertical wall 143 along theouter rim. The vertical wall 143 has a uniform top face that is parallelto the horizontal direction X and the width direction Y. In other words,the vertical wall 143 of the document discharging tray 140 is horizontaland not tilted.

FIG. 6 is an enlarged bottom view of the light-source housing 132 andits vicinity.

FIG. 6 illustrates the document placing tray 130 illustrated in FIG. 2,etc., in bottom view. FIG. 6 is an enlarged view of the light-sourcehousing 132 and its vicinity along the first side 131 a. The lightsource 160 is disposed inside the document placing tray 130 so as toface the light-source housing 132. The light-source housing 132 has anopening 133 in the bottom face of the document placing tray 130. Aportion of the light source 160 is exposed through the opening. Thelight source 160 includes a light emitting element, such as alight-emitting diode (LED). The light from the light source 160 passesthrough the opening 133. The cutout portion 131 of the document placingtray 130 is designed to allow easy access to the space between thedocument placing tray 130 and the document discharging tray 140, andthus, draws the attention of the user when the user removes a document.By disposing the light source 160 near the cutout portion 131, theemission of light is readily noticeable by the user because it isreadily viewed by the user.

FIG. 7 is a schematic side view of the light source 160 arranged inrelation to the document discharging tray 140.

FIG. 7 schematically illustrates the document feeder 120 in view fromthe side of the document discharging tray extension end 140 a. Note thatthe portion of the document discharging tray 140 facing the light source160 is hatched to emphasize the protruding and depressed portions. Inconsideration of the visibility of FIG. 7, only one document G isillustrated on the document discharging tray 140. However, any number ofdocuments G may be disposed on the document discharging tray 140. Thedocument G illustrated in FIG. 7 has the largest length in the widthdirection Y among the lengths of the documents G transportable by thedocument feeder 120.

The protruding portion 141 protruding farther upward than thesurrounding area is disposed at the substantial center of the documentdischarging tray 140 in the width direction Y. The depressed portion 142is disposed adjacent to forward side of the protruding portion 141 (theleft side in FIG. 7). The vertical wall 143 is disposed on the outer rimof the document feeder 120 along the edge on the forward side. In otherwords, the depressed portion 142 is disposed between the vertical wall143 and the protruding portion 141. In the cross-sectional view in FIG.7, the protruding portion 141 is the highest in the height direction Z,the vertical wall 143 is the second highest, and the depressed portion142 is the lowest.

In this embodiment, a portion of the document discharging tray 140 widein the width direction Y constitutes the protruding portion 141. Theprotruding portion 141 has a trapezoidal cross-section. In thecross-sectional view in FIG. 7, the protruding portion 141 has an apexdisposed at a substantially constant height. The end of the protrudingportion 141 in the width direction Y defines a steep edge. The heightdifference between the protruding portion 141 and the depressed portion142 defines an even steeper edge, at which a wall 144 connects theprotruding portion 141 and the depressed portion 142 in the heightdirection Z. Note that the wall 144 and the top face of the protrudingportion 141 do not have to be disposed perpendicular to each other, andmay be disposed at an oblique angle to each other. The upper and loweredges of the wall 144 may be rounded to prevent the document G frombeing stuck.

The protruding portion 141 is disposed slightly rearward to thesubstantial center of the document discharging tray 140 in the widthdirection Y. The length of the protruding portion 141 in the widthdirection Y is smaller than that of the document having the maximumsize. Most of the area of the document G placed on the documentdischarging tray 140 overlays the protruding portion 141 in the widthdirection Y, but a small end portion of the document G extends outwardfrom the end of the protruding portion 141. The portion of the documentG extending over the protruding portion 141 to the forward side isdisposed above the wall 144 and the depressed portion 142, and sagsdownward due to the height difference between the protruding portion 141and the depressed portion 142. This causes the document G is curve in aconvex shape.

The first side 131 a of the cutout portion 131 is disposed atsubstantially the same position as that of the wall 144 in the widthdirection Y. The light source 160 is disposed near the first side 131 a.The light from the light source 160 illuminates the document dischargingtray 140 (the lower portion). The dashed-dotted lines in FIG. 7 indicatethe area illuminated by the light from the light source 160 (irradiationrange SR). The boundary between the protruding portion 141 and thedepressed portion 142 and its vicinity are included in the irradiationrange SR in the width direction Y. Note that the irradiation range SR inthe discharging direction H may be appropriately determined. It isdesirable to establish the irradiation range SR to include both thedocument discharging tray 140 and the document G placed on the documentdischarging tray 140.

A portion of the document discharging tray 140 in the irradiation rangeSR is illuminated with light. This portion includes regions of differentbrightnesses (reflections) depending on the positional with the lightsource 160. In specific, the protruding portion 141, which is disposedclose to the light source 160 in the height direction Z, appearsrelatively bright. In contrast, the depressed portion 142, which isdisposed at a position lower than the protruding portion 141, appearsslightly darker than the protruding portion 141. The wall 144 isdisposed at an angle that is almost parallel to the irradiationdirection of the light from the light source 160. Thus, the wall 144 hasa weak reflection, and appears darker than the depressed portion 142. Aportion of the document G lifted by the protruding portion 141 andcurves. This causes the document G to reflect the light and benoticeable to the user. The document discharging tray 140 not only isilluminated with light from the light source 160 but also provided withthe protruding portion 141 and the depressed portion 142. This causes adifference in the brightness of the irradiation range SR and emphasizesthe incident light. Hence, the user is provided with a better view ofthe document.

As illustrated in FIG. 7, the region including the apex of theprotruding portion 141 and the light source 160 extends in the widthdirection Y to a position on the forward side of the documentdischarging tray 140 corresponding to the edge of a document G having amaximum size. In this way, the light source 160, etc., can be disposedon the forward side of the document feeder 120 to make the document Gstand out and provide the user with a better view.

In the configuration illustrated in FIG. 7, the cutout portion 131 andthe end of the protruding portion 141 (the wall 144) are disposed atsubstantially same positions in the width direction Y. Alternatively,the cutout portion 131 may be disposed farther rearward than the end ofthe protruding portion 141 in the width direction Y. In this way, theprotruding portion 141 can be visible even from a position higher thanthe document feeder 120. Thus, the radiated light is readily noticeable.

In this embodiment, the vertical wall 143, which prevents the document Gfrom falling out, has a shape that allows the user to view the lightilluminating the document discharging tray 140. The vertical wall 143should have a height smaller than the height of the apex of theprotruding portion 141, and larger than the height of the surroundingareas.

The document discharging tray 140 may include an auxiliary tray that canbe pulled out in the downstream direction from the document dischargingtray extension end 140 a to increase the area on which documents are tobe stacked. Such an auxiliary tray does not have to be illuminated withlight from the light source 160. Thus, the auxiliary tray does not haveto be included the irradiation range SR.

In this embodiment, the maximum size of a document is an A3 size(297×420 mm) in which the length in the width direction Y is 297 mm.Note that, for the image forming apparatus 100, the maximum size of thedocument may be an A4 size (297×210 mm) in which the length in the widthdirection Y is 297 mm. In other words, the maximum size of the documenttransportable in the image forming apparatus 100 is determined by thespecifications of the image forming apparatus 100 (document feeder 120).

The cutout portion 131 may be covered with a cover piece. The coverpiece may be transparent or translucent so that the document placedbelow the cutout portion 131 is visible.

Second Embodiment

An image forming apparatus (document feeder) according to a secondembodiments of the present invention will now be described withreference to the accompanying drawings. The structure of the imageforming apparatus according to the second embodiment is substantiallythe same as that of the first embodiment. Thus, the same referencenumerals are used and redundant description and drawings are omitted.

FIG. 8 is a schematic side view of a light source 160 arranged inrelation with a document discharging tray 140 according to a secondembodiment of the present invention.

FIG. 8, like FIG. 7, schematic illustrates a document feeder 120 fromthe side of a document discharging tray extension end 140 a. The portionof the document discharging tray 140 facing the light source 160 ishatched to emphasize the protruding and depressed portions.

The protruding and depressed portions of the document discharging tray140 according to the second embodiment differ from those according tothe first embodiment. In specific, the document discharging tray 140according to the second embodiment has a protruding portion 141, butdoes not have a depressed portion 142. The protruding portion 141 has acurved face 145 at the forward edge that has a slope that increases fromthe top to the bottom. In the first embodiment, the protruding portion141 has the wall 144 that defines a steep edge. In the secondembodiment, the protruding portion 141 has the curved face 145 tosmoothen the edge. The curved face 145 increases the length of theportion that has a gradually varying height in the width direction Y.Thus, documents G having different sizes can be disposed on the documentdischarging tray 140 while extending over the protruding portion 141. Inthis configuration, the face of the protruding portion 141 extending tothe curved face 145 corresponds to an apex. Although not illustrated, avertical wall 143 and a depressed portion 142 may be appropriateprovided in this embodiment.

Third Embodiment

An image forming apparatus (document feeder) according to a thirdembodiments of the present invention will now be described withreference to the accompanying drawings. The structure of the imageforming apparatus according to the third embodiment is substantially thesame as those of the first and second embodiments. Thus, the samereference numerals are used and redundant description and drawings areomitted.

FIG. 9 is a schematic side view of a light source 160 arranged inrelation with a document discharging tray 140 according to the thirdembodiment of the present invention.

FIG. 9, like FIG. 7, schematic illustrates a document feeder 120 fromthe side of a document discharging tray extension end 140 a. The portionof the document discharging tray 140 facing the light source 160 ishatched to emphasize the protruding and depressed portions.

The shape of a protruding portion 141 according to the third embodimentdiffers from that according to the second embodiment. In specific, theprotruding portion 141 according to the third embodiment has a lowprotrusion 146 that is depressed downward relative to an apex orprotrusion top 147. That is, the protruding portion 141 may have anon-uniform height, i.e., an uneven top face. The highest portion of thetop face in the height direction Z defines the protrusion top 147. Inthis embodiment, the low protrusion 146 is a tilted face. Alternatively,the low protrusion 146 may be a groove or a curved face. FIG. 9illustrates the structure including a downward depression.Alternatively, as in the modification illustrated in FIG. 10, theprotruding portion 141 may have upward protrusions.

FIG. 10 is a schematic side view of a light source 160 arranged inrelation with a document discharging tray 140 according to amodification of the third embodiment of the present invention.

According to the modification, a protruding portion 141 has ribs 148protruding upward. In this configuration, the ribs 148 correspond to theapex of the protruding portion 141. The ribs 148 extend along thedischarging direction H on the upper surface of the protruding portion141. In the modification, three ribs 148 are disposed along the widthdirection Y with intervals therebetween. In the case of multiple ribs148, it is desirable that at least one of the ribs 148 be disposed onthe forward side of the center of the document discharging tray 140, andextend to a position on the forward side of the document dischargingtray 140 corresponding to the edge of a document having a maximum size.

Note that the embodiments disclosed herein are illustrative in allrespects and do not serve as a basis for limited interpretation.Therefore, the technical scope of the invention should not beinterpreted only by the above-described embodiments, but should bedefined based on the description of the scope of claims. Meaningsequivalent to the claims and all modifications within the scope areincluded in the technical scope of the invention.

What is claimed is:
 1. A document feeder comprising: a document placingtray on which a document is placed; a transporter transporting thedocument placed on the document placing tray to discharge the documentfrom a document discharging port; a document discharging tray disposedbelow the document placing tray, the document discharged from thedocument discharging port in a discharging direction being stacked inthe document discharging tray; and a light source disposed on thedocument placing tray and radiating light to the document dischargingtray, wherein the document discharging tray includes a protrudingportion protruding farther upward than a surrounding area, and the lightsource is disposed in a region from a center of the document dischargingtray in a width direction orthogonal to the discharging direction to anedge of a document having a maximum size to be discharged, the edge on afront side of the document feeder.
 2. The document feeder according toclaim 1, wherein the light source is disposed in the width direction ina region from an end of the protruding portion on the front side of thedocument feeder to the edge of the document having the maximum size onthe front side of the document feeder.
 3. The document feeder accordingto claim 1, wherein a length of the protruding portion in the widthdirection is smaller than that of the document having the maximum size.4. The document feeder according to claim 1, wherein, the documentplacing tray has a cutout portion on an edge that is located downstreamin the discharging direction and on the front side of the documentfeeder in the width direction, and the light source is disposed on aperipheral edge along the cutout portion.
 5. The document feederaccording to claim 4, wherein the light source is disposed at a positionon the document placing tray within the width of the cutout portion inthe discharging direction.
 6. The document feeder according to claim 4,wherein the cutout portion is so provided in the width direction as toextend farther rearward of the document feeder than an end of theprotruding portion up to a rear side of the document feeder.
 7. Thedocument feeder according to claim 1, wherein a wall vertically erectedis disposed at an end of the protruding portion in the width direction.8. The document feeder according to claim 1, wherein, the documentdischarging tray has a depressed portion depressed farther downward thanthe surrounding area, the depressed portion is disposed adjacent to theprotruding portion in the width direction, and the light source radiateslight to a boundary between the protruding portion and the depressedportion in the width direction.
 9. The document feeder according toclaim 1, further comprising: a vertical wall disposed on the front sideof the document feeder in the width direction along a periphery of thedocument feeder, wherein the vertical wall is lower than an apex of theprotruding portion.
 10. An image forming apparatus comprising thedocument feeder according to claim 1.